1. Field of the Invention
The embodiments described herein relate generally to signaling an end-of-life of a carbon monoxide (CO) sensor and, more particularly, to a method and system for transmitting a CO sensor end-of-life signal of a sensor to a remote agent.
2. Description of the Prior/Related Art
Carbon monoxide (CO) is an odorless, poisonous gas, which can be generated by, for example, gas furnaces, water heaters, ranges, space heaters, wood stoves, cars, portable generators, and gas-powered gardening equipment. Once inhaled, CO inhibits red blood cells from carrying oxygenated blood to the body, thus preventing oxygen from reaching organs in the body. This oxygen deprivation can cause varying amounts of damage depending on a level of exposure. Low level exposure can cause flu-like symptoms including shortness of breath, mild headaches, fatigue, and nausea. However, higher level exposure may cause dizziness, mental confusion, severe headaches, nausea, fainting, or even death.
As public and media awareness of the dangers of CO continue to rise, so does the popularity of devices that detect a presence of CO. The two general types of CO detectors are monitored CO detectors and non-monitored CO detectors. With non-monitored CO detectors, if a threshold level of CO is detected, the non-monitored CO detector sounds an alarm providing occupants of a building, such as residents of a single family house, an apartment building, a condominium or occupants of an office building, for example, an opportunity to ventilate an area or safely leave the building where the high level of CO is detected, much like a common house-hold smoke alarm. Monitored CO detectors, while similar to non-monitored CO detectors, include an advantage of being directly connected to a monitoring company. Therefore, if a high level of CO is detected by the monitored CO detector, the monitored CO detector not only sounds an alarm giving occupants of the building a chance to ventilate an area or safely leave the building, but also transmits an alarm signal to the monitoring company, alerting the monitoring company of the detected high level of CO. The monitoring company verifies the alarm signal, notifies key holders (e.g., occupants), and offers fire, police and/or medical services. Thus, the CO detectors facilitate notifying and/or protecting occupants that are away, sleeping, or already suffering from effects of CO.
In addition to an alarm signal, if another condition is detected by the monitored CO detector, for example, a loss of power to the monitored CO detector, component failure, or an end-of-life of a limited-life sensor, the monitored CO detector transmits a trouble signal to the monitoring company, alerting the monitoring company of the detected condition. Thus, unlike an alarm signal, which is only transmitted when a high level of CO is detected, a trouble signal is transmitted when other preselected conditions such as any one of the above conditions, occur. Further, because an alarm signal and a trouble signal are two separate signals transmitted from a monitored CO detector, the monitoring company can differentiate between the alarm signal and the trouble signal. However, all trouble signals are identical. Thus, when a trouble signal is received by the monitoring company, the monitoring company does not know whether, for example, a loss of power has been detected or an end-of-life of the limited-life sensor has been detected. Knowing which condition has occurred when a trouble signal is received may facilitate an appropriate response by the monitoring company.